Djonlagic Ina, Guo Mengshuang, Matteis Paul, Carusona Andrea, Stickgold Robert, Malhotra Atul
Division of Sleep Medicine Sleep Disorders Research Program Brigham & Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America ; Center for Sleep and Cognition, Department of Psychiatry, Beth Israel Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
Division of Sleep Medicine Sleep Disorders Research Program Brigham & Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America.
PLoS One. 2014 Jan 29;9(1):e85918. doi: 10.1371/journal.pone.0085918. eCollection 2014.
Increasing age is associated with a decline in cognition and motor skills, while at the same time exacerbating one's risk of developing obstructive sleep apnea (OSA). OSA-related cognitive deficits are highly prevalent and can affect various memory systems including overnight memory consolidation on a motor sequence task. Thus, the aim of our study was to examine the effect of aging on sleep-dependent motor memory consolidation in patients with and without OSA.
We studied 44 patients (19-68 years) who had been referred by a physician for a baseline polysomnography (PSG) evaluation. Based on their PSG, patients were assigned either to the OSA group (AHI>5/h), or control (Non-OSA) group (AHI<5/h). All subjects performed the Psychomotor Vigilance Task (PVT) and the Motor Sequence Learning Task (MST) in the evening and again in the morning after their PSG.
Despite similar learning in the evening, OSA subjects showed significantly less overnight improvement on the MST, both for immediate (OSA -2.7% ± 2.8% vs. controls 12.2% ± 3.5%; p = 0.002) and plateau improvement (OSA 4.9% ± 2.3% vs. controls 21.1%± 4.0%; p = 0.001). Within the OSA group, there was a significant negative correlation between overnight MST improvement and age (r(2) = 0.3; p = 0.01), an effect that was not observed in the Non-OSA group (r(2) = 0.08; p = 0.23).
Consistent with previous research, healthy sleepers demonstrated a higher degree of sleep-dependent overnight improvement on the MST, an effect not mitigated by increasing age. However, the presence of untreated obstructive sleep apnea is associated with an aging-related cognitive deficit, otherwise not present in individuals without OSA. As other research has linked the presence of OSA to a higher likelihood of developing dementia, future studies are necessary to examine if the inhibition of memory consolidation is tied to the onset of neurodegenerative disease.
年龄增长与认知和运动技能下降相关，同时会增加患阻塞性睡眠呼吸暂停（OSA）的风险。与OSA相关的认知缺陷非常普遍，会影响各种记忆系统，包括运动序列任务中的夜间记忆巩固。因此，我们研究的目的是检查衰老对有和没有OSA的患者睡眠依赖的运动记忆巩固的影响。
我们研究了44名（19 - 68岁）因基线多导睡眠图（PSG）评估而被医生转诊的患者。根据他们的PSG结果，患者被分为OSA组（呼吸暂停低通气指数>5次/小时）或对照组（非OSA组，呼吸暂停低通气指数<5次/小时）。所有受试者在晚上进行了心理运动警觉任务（PVT）和运动序列学习任务（MST），并在PSG检查后的早上再次进行。
尽管晚上的学习情况相似，但OSA受试者在MST上的夜间改善明显较少，无论是即时改善（OSA组 -2.7% ± 2.8%，对照组12.2% ± 3.5%；p = 0.002）还是平台期改善（OSA组4.9% ± 2.3%，对照组21.1% ± 4.0%；p = 0.001）。在OSA组中，夜间MST改善与年龄之间存在显著负相关（r(2) = 0.3；p = 0.01），而在非OSA组中未观察到这种效应（r(2) = 0.08；p = 0.23）。
与先前的研究一致，健康睡眠者在MST上表现出更高程度的睡眠依赖夜间改善，这种效应不会因年龄增长而减弱。然而，未经治疗的阻塞性睡眠呼吸暂停的存在与衰老相关的认知缺陷有关，而在没有OSA的个体中不存在这种情况。由于其他研究已将OSA的存在与患痴呆症的更高可能性联系起来，未来有必要进行研究以检查记忆巩固的抑制是否与神经退行性疾病的发病有关。
